Incomplete join on query using course_modules #8
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…t size and errors. Code appeared to assume idnumber was unique.
terrycampbell
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The course_modules join is incomplete. It would work only if idnumber were a unique index, but the index requires course,idnumber to be unique. In an application where module idnumbers are repeated (for example when courses are being cloned) this results in incorrect joins, large result size and possible connection aborts. The fix is to require a match on both idnumber and course.